If you go round ones make them like a polstyrene cup shape this will help it come out of the mould easier ,you have along way to go but you have come sofar ,good to see you have made the effort to be original ,its not easy and alot of cash will be spent be 100% happy with the product before you make the mould as moulds can be expensive little buggers to make ..
I see this is harrys old 1200 what happend to the front bar from it ,cheers geoff